Flashlight with automatic time-delay cut-off switch



OCL ZO', 1970 R, MALLQRY 3,535,282

FLASHLIGHT WITH AUTOMATIC TIME-DELAY CUT-OFF SWITCH Filed March 5,. 19692 Sheets-Sheet 2 72/ g/ I/IZ/l/ INVENTOR.

United States Patent 3,535,282 FLASHLIGHT WITH AUTOMATIC TIME-DELAYCUT-OFF SWITCH Henry Rogers Mallory, Greenwich, Conn., assignor to P. R.Mallory & Co., Inc., Indianapolis, Ind., a corporation of Delaware FiledMar. 3, 1969, Ser. No. 803,800 Int. Cl. F21v 23/ 04 US. Cl. 200-60Claims ABSTRACT OF THE DISCLOSURE The flashlight switch is operable by arear cap that is movable axially forward on the cylindrical housing forthe battery.

A compression spring and an enclosing bellows are disposed in thehousing and are compressed in the switch closing operation. An orificeat one end of the bellows, otherwise closed, is controlled by a leakyvalve which permits air to enter and refill the bellows to normal fullopen position under expanding force and movement of the compressedspring, seeking to return to its normal condition. In the compressedposition of the bellows and the spring, the switch to the flashlight isclosed; and in the open position of the bellows and permitted expandedposition of the compression spring, the switch is opened to open thecircuit from the battery to the lamp. The bellows and the compressionspring thus operate as an automatic device to open the light circuitafter a predetermined period of time, determined by the valve, when theflashlight is left unattended or forgotten.

This invention relates to flashlights, and, particularly, to flashlightsprovided with an automatic self-opening mechanism for opening the switchcircuit that is usually provided for manual operation to connect thelamp to the battery cell or cells in the flashlight housing.

A flashlight is conventionally provided with a manually operable switchthat connects the lamp to the battery in a closed circuit, and isstationary and remains closed until it is manually shifted to openposition by the operator of the flashlight.

if the flashlight is operated to lighted condition and then left orforgotten, the switch will remain closed and the battery will be drainedto destruction,

The object of this invention is to provide an automatic switch that willopen after a predetermined interval of time, following the closure ofthe switch to connect the light and the battery, if the switch is notmanually operated to open position before the end of that time interval.

In that manner, the battery is protected against being connected to thelamp too long without any beneficial use, and the switch will be openedto prevent destruction of the battery.

Another object of the invention is to provide a flashlight with a switchthat opens automatically, and that is controlled by a simple time delaymechanism, that is efficient and constant in its operation, and that iseasy to manufacture and to assemble in the flashlight.

The time measuring and delay device which permits the switch to remainclosed for a specific limited time, without external reoperation,consists of a tubular element, of rubbery material, which can becompressed axially into bellows shape, of axially shortened dimension.The inner' end of the bellows is closed by a circular metal plate toserve as an end wall for the bellows, and as a conducting element in thebattery circuit to the lamp. The outer end of the bellows contains asmall coaxial orifice, which is controlled by a small ball valve ofporous material to permit free fast egress of the air from the bellowswhen 3,535,282 Patented Oct. 20, 1970 ice the bellows is compressed, andto control ingress of air into the bellows to a very slow air stream,thereby establishing a relatively long time interval for refilling thebellows with air to permit it to reassume its original elongatedair-filled condition, and to open the switch.

Within the bellows two helical spring elements are provided. One springelement serves as a compression spring which is compressed when thebellows element is compressed, and then serves to push the bellows backto extended air-filled condition. The other helical spring serves as acompressible contact so that it may remain engaged against thecooperating contact during the preliminary restoring movement of thecompression spring that pushes the bellows cylinder back to extendedair-filled position. The details of construction and the manner ofoperation of the flashlight constructed in accordance with theprinciples of this invention are explained more fully in the followingspecification, taken in connection with the accompaying drawings, inwhich:

FIG. 1 is a longitudinal view of the flashlight embodying thisinvention, with the cylindrical housing shown open and portions of thestructure shown in elevation and portions shown in section; in fullyextended position with the flashlight switch open;

FIG. 2 is a corresponding view of the flashlight in FIG. 1, showing onlythe rear section with the delay mechanism compressed to place the switchin circuitclosing position to energize the lamp, and shows the tubularrubber cylinder compressed as a bellows with the air 'valve in closingposition.

FIG. 3 is a longitudinal sectional view of a supporting and guide canfor the rubber bellows, and shows the porous valve button that controlsthe air flow through the orifice of the bellows member; and

FIG. 4 is an axial end view taken along lead line 3-3 from the open endof the can in FIG. 3, to show more fully the manner in which the airvalve is supported on a cantilevered spring to rest against the openingor orifice in the other end of the bellows member.

As shown generally, in FIGS. 1 and 2, the flashlight 10 constructed inaccordance with the principles of this invention, comprises a lamp 12, atransparent lens 13, a battery 14 for energizing the lamp, a switchassembly 16, for controlling the circuit including the lamp 12 and thebattery 14, a housing 18 for enclosing and supporting the foregoingcomponents of the flashlight, and a rear end operating cap 20, fittedover the outer rear end of the housing 18, for actuating the switch 16,and a time delay mechanism 22, for automatically opening the switchmechanism following a predetermined interval after the switch is closed,if the switch is not otherwise manually operated to open position at theend of that time interval.

The lamp 12 is seated in a compartment at the front end of the housing18, closed by the transparent lens 13. The lamp is conventional and isconventionally threaded in a socket 26, that is electrically andmechanically secured to the front wall 28 of the housing 18. The centerelectrode 32 of the battery 14 is coaxially disposed to be pressedagainst the inner axial terminal of the lamp 12 in conventional manner.

The battery 14 is shown as a single body which may have one or more cellunits and is coaxially disposed in the housing 18. The pressure on therear of the battery 14 is established by a metallic button 34 having abackwardly extending coaxial stub 36, to which a helically roundmetallic spring 38 is electrically connected by gripping of two or threeof the convolutions at the end of the spring 38 on the stub 36. Aninsulating washer 40 rests against the shoulder 42 on the button 34 andserves as a bracing element for the front end convolution 38A of thespring 38. The bracket end convolution of the spring 38 is seated in andcrimped in a circular metal plate 44. That plate serves the purpose ofholdin the spring 38 in proper axially aligned position, as a mechanicalfunction, and also serves an electrical function by constituting anelectrical terminal for the rear end of that spring 38 to engage a metalcap 46 that serves as a stationary terminal for the switch mechanismgenerally indicated at 16. That cap 46 is disposed and fixedly held in apredetermined position within the housing, and transversely to the axis.

As previously mentioned, the switch mechanism 16 is controlled by thetime delay device 22, which is shown in open expanded switch openposition in FIG. 1, and is shown in contracted switch-closing positionin FIG. 2.

The time delay device 22 comprises a normally airfilled bag 50 ofneoprene or rubber or the like, which is structurally closed at itsinner end, by a construction in volving the metal cap 46, and that bag50 is provided with a small orifice 52 at its outer end, through whichair may be forced freely out of the neoprene bag 50. Later, air ispermitted to enter bag 50 under valve-controlled conditions in order torefill the bag as the bag is expanded to its normal full air-filledcondition. Within the neoprene bag 50, two springs 54 and 56 aredisposed, which are arranged to be compressed when the neoprene bag 50is compressed.

Spring 56 is an element of the switch circuit, and is anchored at oneend, with its other end free to serve as the movable contact of theswitch to engage metal cap 46 as the fixed contact. The spring 54 is apower spring, and is under some initial compression in order to hold theneoprene bag open under normal conditions. When the neoprene bag iscompressed to its accordion-pleated shape, as in FIG. 2, spring 54serves two purposes. First, during compression, spring 54 serves toposition the accordion pleats or folds that are formed in the neoprenebag 50 as that bag is compressed. Then the spring 54, as so compressed,serves to reexpand the neoprene bag to its air-filled condition, at arate that is controlled by the rate of reentrance of air into theneoprene bag to refill the bag. Such air ingress is controlled by avalve 58,

' which consists of a simple hemispherical porous ball 60 mounted at thefree end of a cantilever spring 62, and so disposed that the ball 60normally seats on the rim of the orifice 52 in such manner that thereentrance of air into the neoprene bag is through porous ball 60, andtherefore is controlled practically entirely by the porous structure ofthe porous ball 60.

The cantilever spring 62 is supported on a guiding and supporting can64, which provides reinforcing backing for the neoprene bag in its fullopen position, and which provides support for the cantilever spring 62which carries and supports the porous ball 60. The neoprene bag 50 isprovided with an outer end wall 66. That end wall 66 of bag 50 issuitably supported and braced by an annular seating ring 68, that isformed as an annular coaxial ring, pressed inwardly from the outer wallof the metal can 64. The can 64 has an extended cylindrical body 70,which serves as a guiding, limiting and reinforcing outer wall for therearward portion of the neoprene bag 50, during its compression andreexpansion. The inner end of the metal can 64 is also provided with anannular peripheral flange 72 which serves as a guide for the can duringcertain inward movement of the can to close the switch, and as alimiting stop for the can 64 when the can 64 is moved outward by thesubsequent outward movement of the neoprene bag 50 as it is beingrefilled with air during the restoring action of the restoringcompression spring 54.

Movement of the metal can 64 inwardly to compress the spring 54 servesto close the main switch for the flashlight, and in such inward movementof the can is established by axial movement of a plastic back end button76 which is mechanically locked onto the metal can 64 by '4 means of abearing ring 78, which is initially cylindrical, as shown in FIG. 3, butis peened over to form a flange 80, as shown in FIGS. 1 and 2, to lockthe plastic button 76 mechanically and securely onto the metal can 64.

When the back end button 76 is pressed axially for Ward, three thingsoccur. First, the initially compressed spring 54 is further compressedso it may later function to force the can 64 with its button 76 andneoprene bag backward, and axially outward, to restore the bag toair-filled condition. Second, the forward manual compression of theswitch-closing button 76 also moves the contact spring 56 axiallyforward, so its free inner end con volution 56A will engage the metalliccircular plate 46, previously referred to as one electrode of theswitch. The end convolution 56A of contact spring 56 serves as themovable electrode to engage that stationary electrode, the plate 46. Thecompressibility of contact spring 56 permits contact to be made between56A and plate 46, immediately upon operation of the plastic button 76 atthe end of the flashlight, and the compressibility of the spring 56takes up any lost motion otherwise necessary to accommodate the inwardmovement of the outer end wall of the neoprene bag 50 and the metal can64. The third thing that is done by forward movement of the back endbutton is the accordion folding of the rubber bag 50. Those folds dropin between the convolutions of spring 54, as in FIG. 2.

The outer end convolution 54A of the power compression spring 54 restsagainst a metallic washer 55, which engages the inner surface of the endwall of neoprene bag 50, and takes the pressure of the compressionspring 54, and protects the surface of the end wall 66 of the neoprene 1bag 50 from injury. The inner free or floating end of the contact spring56 is supported due to its back end convolution being suitably securedand anchored coaxially to the supporting and bracing washer 55 that isheld in place by the power compression spring 54.

The front end convolution 54A at the inner end of the power compressionspring 54 is appropriately anchored to the inner peripheral edge of theneoprene bag, including cap 46, so the bag and the springs can behandled as an assembled sub-unit for convenient handling and assembly inmaking up the flashlight structure.

As shown in FIGS. 1 and 2, the front end convolution 54A of power spring54 rests on a circular arcuate seat of an annular seating ring 86, forgood electrical circuit conduction. The seating ring 86 is part of ametallic tubular electrically conducting element 88 which is adapted tobe fitted snugly into the metallic housing 18 of the flashlight, or toengage a thin copper conducting strip that may alternatively be disposedlengthwise within the housing if an insulating housing is employed.

Electrical conductivity is thus established from the battery frontterminal through the lamp 12, then through the housing 18, the tubularelement 88, the power spring 54, metallic washer 55, contact spring 56to front convolution 56A of contact spring 56, as the movable switchcontact.

The annular supporting ring 86 and the end of the neoprene rubber bag50, and the end convolution 54A of the power spring 54 are then tightlycoupled in crimped relationship by and on an annular crimping plate 92,of insulating material. Plate 92 has a transverse annular plate 94 witha central axial opening 96, and peripheral crimping fingers 98, whichare crimped to lock the open peripheral end edge of the neoprene bagtightly in position in engagement with the end convolution 54A of thecompression power spring 54, by a back-up metallic crimping ring plate46, which was previously referred to as the stationary contact of theswitch.

The crimping insulation fingers 98 are shaped and spaced to extendthrough openings or window slots 102 in the end wall 104 of the tubularelement 88, to be then bent over to press the end edge of the rubber bag50 tightly against the end convolution 54A, and to be held in suchcrimping position by similar metallic crimping fingers 46A of themetallic crimping ring plate 46. The crimping fingers of the metallicring plate 46 also extend through the window slots 102, butappropriately spaced to avoid electrical contact with the metal of thetubular element 88. The crimping ring plate 46 is engaged by plate 44,and serves as the stationary switch terminal with the potential of therear surface of the battery. Any air leakage will be slight and notharmful since the effect would be merely to reduce the cut-off intervalof the delay mechanism.

The central axial opening 96 in the insulating plate 94 and the centralaxial opening of the circular seat 85, 86 for the convolution 54A,permit axial movement of contact spring 56 to engage the stationaryswitch contact, the switch plate 46.

In order to hold switch plate 46 in fixed position, a guide cylinder 110of insulating material is slip-fitted into the housing 18, from the openend of the housing, as a sub-assembly into which the neoprene bag 50,the two springs 54 and 56, the guide can 70, and the elements at theinner end of the bag have been previously assembled. The end cap 76 willalso have been assembled on the can 70 and said guide cylinder 110, inthe manner shown in FIG. 1.

That guide cylinder 110, of thermo plastic or resinous material, isorginally formed with axially or longitudinally projecting end fingers112, to extend through window slots in the tubular element 88, disposedperipherally around the tubular element 88. That cylinder 110 thusserves as a housing for the assembly. When appropriately assembled, theprojecting end fingers 112 are heated and peened over to seal thehousing 110' on the assembly. The entire assembly, including the housing110 and the cap 76 may thus be appropriately positioned in the end of ofthe main flashlight housing 18.

As previously explained, upon compression of the end cap 76, theneoprene bag 50 and the springs 54 and 56 will be compressed, and air inthe bag 50 will be expelled through the orifice and freely past theporous ball 60. The spring 62 will then force ball to its seat, and aircan reenter the bag practically only through the ball 60, thuscontrolling the bag refilling and expansion in response to expansionpressure of the compressed spring 54. In the meantime, contact spring 56at convolution 56A remains in contact with plate 46 until bag 50 refillsto pull spring contact 56A away from plate 46.

The invention thus discloses an automatic time delay device for openingthe lamp circuit of a flashlight after a predetermined time intervalfollowing the closure of the switch, in case the switch is not manuallyopened before the termination of that interval.

It will be understood that variations may be made in the details ofconstruction and arrangement, without departing from the spirit andscope of the invention as described, and as defined in the claims.

What is claimed is:

1. A flashlight with a built-in turn-off switch, comprising a hollowcylindrical housing having a front space in said housing to receive acylindrical battery coaxially disposed within and near one end of thehousing, the battery normally having two end faces, with a terminal oneach end face;

means for supporting a lamp at the front end of the housing, which lampwill have two terminals, one lamp terminal to engage the battery frontterminal on the front end face of the battery, and the other lampterminal to engage a metal conductor means extending back along thelength of the housing;

switch means on said housing having an open and a closed position;

manually operable means on said housing for operating said switch meansto electrically connect said lamp to the battery in closed circuit;

and means associated with said switch means for opening said switchmeans automatically after the lapse of a predetermined time interval, ifsaid switch is left in closed position longer than said time interval.

2. A flashlight as in claim 1, in which said manually operable meansserves to prime said automatic opening means each time the switch meanseach time the switch means is moved to closed position.

3. A flashlight with built-in turn-oif switch as in claim 1, in whichsaid means for opening said switch automatically includes:

a collapsible air container having an air-full and an airempty position;

means for compressing the container from air-full position to air-emptyposition to express the air from said container;

a compression spring normally tending to hold the container expanded toair-full position, said spring being compressed by and when saidcompressing means is operated to compress said container to air-emptyposition, and said compression spring serving then to reexpand saidcontainer to air-full position;

and valve means on said container for permitting free air outflow whensaid container is compressed, but restricting air return inflow whensaid compression spring reexpands the compressed container to air-fullposition.

4. A flashlight with built-in turn-off switch, as in claim 3, in whichsaid collapsible container consists of an elongated cylindrical bag, ofair-impervious material, having its back end wall completely closed witha rigid closure cap, and having its front end wall substantially closedexcept for a small orifice for air passage into and out of saidcontainer;

a rigid bracing washing plate is disposed to rest against the innersurface of said front end wall;

and said compression spring is disposed within said bag to rest one endagainst said rigid bracing washer plate at the front end wall and theother end of said spring rests against said closure cap at the back endwall;

and said valve means is disposed at said orifice to control the airpassage into and out of said collapsible container.

5. A flashlight with a built-in turn-off switch, as in claim 1, in whichsaid means for automatically opening said switch means include acollapsible bag of air-impervious material,

means for collapsing said bag when operating said switch means to closedposition,

means for restoring said bag to normal air-full position and thereuponoperating said switch means to open position,

and means for controlling the time required to restore said bag tonormal air-full position, to thereby control the duration of time thatthe switch means will be permitted to remain in closed position withoutfurther manual operation.

6. A flashlight with built-in turn-off switch, as in claim 5, in whichsaid time-controlling means includes an orifice in the wall of said bag,and means for controlling the passage of air into said bag through saidorifice.

7. A flashlight with a built-in turn-off switch, as in claim 5, in whichmeans disposed within the bag serves to direct and to position pleatsformed in the bag maerial as the bag is compressed to accordion shape.

8. A flashlight, as in claim 1, including, further,

an insulating guide sleeve co-axially disposed in said housing at itsback end, with a peripheral outer end face extending axially beyond saidhousing;

an end cap fitted coaxially over said peripheral outer end face andmanually movable coaxially inwardly, over said outer end face, fromouter position to inner position, to operate said switch means;

means associated with said automatic switch Opening means of claim 1 formoving said end cap back to outer position;

and means on said end cap cooperating with said guide sleeve to limitthe extent of movement of said end cap to its outer position.

9. In a flashlight structure, as in claim 1,

time-delay switch-opening mechanism comprising a contact button toengage one end face terminal of a flashlight battery in place;

a helical metallic spring having one end grippingly coupled to saidcontact button and the other end electrically engaging a bracing wall ofelectrically conducting metal;

an insulating support for said bracing electrically conducting metalWall;

an air-impervious bag relatively elongated along an axial dimension andopen at its inner end;

means peripherally supporting said open inner end of said bag adjacentsaid electrically conducting metal wall;

a compressible spring having one end fixedly braced against saidelectrically conducting metal wall and the other end braced against areinforcing plate at the outer coaxial end of said air-impervious bag;

a pressure element disposed adjacent said outer end of said bag forcoaxially compressing said bag;

switch contact means supported from said outer end of said bag andoperative to engage said electrically conducting wall when said bag isaxially compressed and the air expelled therefrom;

and valve means for permitting free egress of air from said bag uponcompression of the bag, and for controlling timed ingress of air intosaid bag upon reexpansion to air-full condition. 10. A flashlighttime-delay switch, to open a flashlight battery circuit, said switchcomprising a generally cylindrical collapsible bag generally open at itsinner end and closed at its outer end except for a small orifice foregress and ingress of air;

electrically conductive means for supporting said inner end of said bagto be held in generally circular normal form, and for also closing saidinner end of the bag against air passage;

means for collapsing said bag to cause egress of air through saidorifice and for moving one end of said bag toward the other end;

switch means supported at the outer end of said bag and movabletherewith to engage said electrically conductive supporting means at theinner end of said bag to complete an electric circuit of the flashlight;

means for restoring said bag to its expanded condition;

and valve means at said small orifice for controlling the passage of airtherethrough for controlling the time required to refill the bag to itsexpanded condition.

References Cited UNITED STATES PATENTS 2,630,517 3/1953 Hiscar 219-220XR 2,784,290 3/1957 Asaton 200 XR 3,259,713 7/1966 Herridge, et a1.20033 XR ROBERT K. SCHAEFER, Primary Examiner J. R. SCOTT, AssistantExaminer US. Cl. X.R. 20033, 83

